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-rw-r--r--lib_generic/lmb.c280
1 files changed, 280 insertions, 0 deletions
diff --git a/lib_generic/lmb.c b/lib_generic/lmb.c
new file mode 100644
index 0000000..3b8c805
--- /dev/null
+++ b/lib_generic/lmb.c
@@ -0,0 +1,280 @@
+/*
+ * Procedures for maintaining information about logical memory blocks.
+ *
+ * Peter Bergner, IBM Corp. June 2001.
+ * Copyright (C) 2001 Peter Bergner.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <common.h>
+#include <lmb.h>
+
+#define LMB_ALLOC_ANYWHERE 0
+
+void lmb_dump_all(struct lmb *lmb)
+{
+#ifdef DEBUG
+ unsigned long i;
+
+ debug("lmb_dump_all:\n");
+ debug(" memory.cnt = 0x%lx\n", lmb->memory.cnt);
+ debug(" memory.size = 0x%08x\n", lmb->memory.size);
+ for (i=0; i < lmb->memory.cnt ;i++) {
+ debug(" memory.reg[0x%x].base = 0x%08x\n", i,
+ lmb->memory.region[i].base);
+ debug(" .size = 0x%08x\n",
+ lmb->memory.region[i].size);
+ }
+
+ debug("\n reserved.cnt = 0x%lx\n", lmb->reserved.cnt);
+ debug(" reserved.size = 0x%08x\n", lmb->reserved.size);
+ for (i=0; i < lmb->reserved.cnt ;i++) {
+ debug(" reserved.reg[0x%x].base = 0x%08x\n", i,
+ lmb->reserved.region[i].base);
+ debug(" .size = 0x%08x\n",
+ lmb->reserved.region[i].size);
+ }
+#endif /* DEBUG */
+}
+
+static unsigned long lmb_addrs_overlap(ulong base1,
+ ulong size1, ulong base2, ulong size2)
+{
+ return ((base1 < (base2+size2)) && (base2 < (base1+size1)));
+}
+
+static long lmb_addrs_adjacent(ulong base1, ulong size1,
+ ulong base2, ulong size2)
+{
+ if (base2 == base1 + size1)
+ return 1;
+ else if (base1 == base2 + size2)
+ return -1;
+
+ return 0;
+}
+
+static long lmb_regions_adjacent(struct lmb_region *rgn,
+ unsigned long r1, unsigned long r2)
+{
+ ulong base1 = rgn->region[r1].base;
+ ulong size1 = rgn->region[r1].size;
+ ulong base2 = rgn->region[r2].base;
+ ulong size2 = rgn->region[r2].size;
+
+ return lmb_addrs_adjacent(base1, size1, base2, size2);
+}
+
+static void lmb_remove_region(struct lmb_region *rgn, unsigned long r)
+{
+ unsigned long i;
+
+ for (i = r; i < rgn->cnt - 1; i++) {
+ rgn->region[i].base = rgn->region[i + 1].base;
+ rgn->region[i].size = rgn->region[i + 1].size;
+ }
+ rgn->cnt--;
+}
+
+/* Assumption: base addr of region 1 < base addr of region 2 */
+static void lmb_coalesce_regions(struct lmb_region *rgn,
+ unsigned long r1, unsigned long r2)
+{
+ rgn->region[r1].size += rgn->region[r2].size;
+ lmb_remove_region(rgn, r2);
+}
+
+void lmb_init(struct lmb *lmb)
+{
+ /* Create a dummy zero size LMB which will get coalesced away later.
+ * This simplifies the lmb_add() code below...
+ */
+ lmb->memory.region[0].base = 0;
+ lmb->memory.region[0].size = 0;
+ lmb->memory.cnt = 1;
+ lmb->memory.size = 0;
+
+ /* Ditto. */
+ lmb->reserved.region[0].base = 0;
+ lmb->reserved.region[0].size = 0;
+ lmb->reserved.cnt = 1;
+ lmb->reserved.size = 0;
+}
+
+/* This routine called with relocation disabled. */
+static long lmb_add_region(struct lmb_region *rgn, ulong base, ulong size)
+{
+ unsigned long coalesced = 0;
+ long adjacent, i;
+
+ if ((rgn->cnt == 1) && (rgn->region[0].size == 0)) {
+ rgn->region[0].base = base;
+ rgn->region[0].size = size;
+ return 0;
+ }
+
+ /* First try and coalesce this LMB with another. */
+ for (i=0; i < rgn->cnt; i++) {
+ ulong rgnbase = rgn->region[i].base;
+ ulong rgnsize = rgn->region[i].size;
+
+ if ((rgnbase == base) && (rgnsize == size))
+ /* Already have this region, so we're done */
+ return 0;
+
+ adjacent = lmb_addrs_adjacent(base,size,rgnbase,rgnsize);
+ if ( adjacent > 0 ) {
+ rgn->region[i].base -= size;
+ rgn->region[i].size += size;
+ coalesced++;
+ break;
+ }
+ else if ( adjacent < 0 ) {
+ rgn->region[i].size += size;
+ coalesced++;
+ break;
+ }
+ }
+
+ if ((i < rgn->cnt-1) && lmb_regions_adjacent(rgn, i, i+1) ) {
+ lmb_coalesce_regions(rgn, i, i+1);
+ coalesced++;
+ }
+
+ if (coalesced)
+ return coalesced;
+ if (rgn->cnt >= MAX_LMB_REGIONS)
+ return -1;
+
+ /* Couldn't coalesce the LMB, so add it to the sorted table. */
+ for (i = rgn->cnt-1; i >= 0; i--) {
+ if (base < rgn->region[i].base) {
+ rgn->region[i+1].base = rgn->region[i].base;
+ rgn->region[i+1].size = rgn->region[i].size;
+ } else {
+ rgn->region[i+1].base = base;
+ rgn->region[i+1].size = size;
+ break;
+ }
+ }
+
+ if (base < rgn->region[0].base) {
+ rgn->region[0].base = base;
+ rgn->region[0].size = size;
+ }
+
+ rgn->cnt++;
+
+ return 0;
+}
+
+/* This routine may be called with relocation disabled. */
+long lmb_add(struct lmb *lmb, ulong base, ulong size)
+{
+ struct lmb_region *_rgn = &(lmb->memory);
+
+ return lmb_add_region(_rgn, base, size);
+}
+
+long lmb_reserve(struct lmb *lmb, ulong base, ulong size)
+{
+ struct lmb_region *_rgn = &(lmb->reserved);
+
+ return lmb_add_region(_rgn, base, size);
+}
+
+long lmb_overlaps_region(struct lmb_region *rgn, ulong base,
+ ulong size)
+{
+ unsigned long i;
+
+ for (i=0; i < rgn->cnt; i++) {
+ ulong rgnbase = rgn->region[i].base;
+ ulong rgnsize = rgn->region[i].size;
+ if ( lmb_addrs_overlap(base,size,rgnbase,rgnsize) ) {
+ break;
+ }
+ }
+
+ return (i < rgn->cnt) ? i : -1;
+}
+
+ulong lmb_alloc(struct lmb *lmb, ulong size, ulong align)
+{
+ return lmb_alloc_base(lmb, size, align, LMB_ALLOC_ANYWHERE);
+}
+
+ulong lmb_alloc_base(struct lmb *lmb, ulong size, ulong align, ulong max_addr)
+{
+ ulong alloc;
+
+ alloc = __lmb_alloc_base(lmb, size, align, max_addr);
+
+ if (alloc == 0)
+ printf("ERROR: Failed to allocate 0x%lx bytes below 0x%lx.\n",
+ size, max_addr);
+
+ return alloc;
+}
+
+static ulong lmb_align_down(ulong addr, ulong size)
+{
+ return addr & ~(size - 1);
+}
+
+static ulong lmb_align_up(ulong addr, ulong size)
+{
+ return (addr + (size - 1)) & ~(size - 1);
+}
+
+ulong __lmb_alloc_base(struct lmb *lmb, ulong size, ulong align, ulong max_addr)
+{
+ long i, j;
+ ulong base = 0;
+
+ for (i = lmb->memory.cnt-1; i >= 0; i--) {
+ ulong lmbbase = lmb->memory.region[i].base;
+ ulong lmbsize = lmb->memory.region[i].size;
+
+ if (max_addr == LMB_ALLOC_ANYWHERE)
+ base = lmb_align_down(lmbbase + lmbsize - size, align);
+ else if (lmbbase < max_addr) {
+ base = min(lmbbase + lmbsize, max_addr);
+ base = lmb_align_down(base - size, align);
+ } else
+ continue;
+
+ while ((lmbbase <= base) &&
+ ((j = lmb_overlaps_region(&(lmb->reserved), base, size)) >= 0) )
+ base = lmb_align_down(lmb->reserved.region[j].base - size,
+ align);
+
+ if ((base != 0) && (lmbbase <= base))
+ break;
+ }
+
+ if (i < 0)
+ return 0;
+
+ if (lmb_add_region(&(lmb->reserved), base, lmb_align_up(size, align)) < 0)
+ return 0;
+
+ return base;
+}
+
+int lmb_is_reserved(struct lmb *lmb, ulong addr)
+{
+ int i;
+
+ for (i = 0; i < lmb->reserved.cnt; i++) {
+ ulong upper = lmb->reserved.region[i].base +
+ lmb->reserved.region[i].size - 1;
+ if ((addr >= lmb->reserved.region[i].base) && (addr <= upper))
+ return 1;
+ }
+ return 0;
+}
generated by cgit v1.1 at 2024-11-23 05:47:07 +0000